US4038593A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Regulated high voltage ac power supply with regulated d.c. bias current
Assignee: Xerox Corp
•
Filing: 1975-09-26
•
Granted: 1977-07-26
•
Expires: 1995-09-26
Abstract
Abstract A circuit for concurrently producing regulated high voltage a.c. current and bias d.c. current on one output line, where all regulation is accomplished in low voltge circuits, power supply being particularly useful as the power source for copier and duplicator corotrons. The basic wave shape is a rectangular wave which is amplified and regulated for application as the a.c. input to a corotron. The corotron itself is used as the rectifier for the d.c. bias current, with this current being variable in either the positive or negative direction by varying the symmetry of the a.c. rectangular wave. Since the part of the wave which has the shorter duration must have the higher amplitude, and current in the corotron increases with voltage, a feedback loop which controls the rectangular wave duty cycle will regulate the d.c. bias current as well.
Inventors
- 👤 Halsey P. Quinn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 14:14
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/02; G03G15/0266; H; H02; H02M; H02M5/00; H02M5/40; H02M5/42; H02M5/44; H02M5/453; H02M5/458; H02M7/00; H02M7/42; H02M7/44; H02M7/48; H02M7/53; H02M7/537; H02M7/538; H02M7/53803; H02M7/53806
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
122 words
An a.c. and d.c. power supply for driving a non-linear load in which current over the operating voltage range increases faster or slower than applied voltages comprising: generating means for generating non-symmetrical a.c. voltage waveshape, a transformer for coupling said a.c. waveshape from said generating means to said load such that the sum of all instantaneous positive and negative a.c. voltages at said load will be approximately zero, d.c. feedback means for sensing the d.c. current at said load produced by the application of said non-symmetrical a.c. voltage to said non-linear load, and for producing and coupling to said generating means a correction signal to vary the symmetry of said a.c. waveshape to regulate said load d.c. current to a pre-determined level.
Claim 2
Dependent Claim
122 words
An a.c. and d.c. power supply for driving a non-linear load in which current over the operating voltage range increases faster or slower than applied voltages comprising: generating means for generating non-symmetrical a.c. voltage waveshape, a transformer for coupling said a.c. waveshape from said generating means to said load such that the sum of all instantaneous positive and negative a.c. voltages at said load will be approximately zero, d.c. feedback means for sensing the d.c. current at said load produced by the application of said non-symmetrical a.c. voltage to said non-linear load, and for producing and coupling to said generating means a correction signal to vary the symmetry of said a.c. waveshape to regulate said load d.c. current to a pre-determined level.
Claim 3
Dependent Claim
17 words
The apparatus of claim 1 wherein said generating means generates an a.c. waveshape that is substantially rectangular.
Claim 4
Dependent Claim
11 words
The apparatus of claim 1 wherein said load is a corotron.
Claim 5
Dependent Claim
48 words
The apparatus of claim 3 wherein said generating means comprises: a rectangular wave generator, and amplifier means for amplifying said rectangular wave, and for coupling said rectangular wave to said transformer, and wherein said correction signal from said d.c. feedback means is coupled to said rectangular wave generator.
Claim 6
Dependent Claim
47 words
The apparatus of claim 4 further comprising: a.c. feedback means for sensing the a.c. voltage at said load, and for producing and coupling to said amplifier means a correction signal to vary the amplification of said amplifier means to regulate said a.c. voltage to a pre-determined level.
Claim 7
Dependent Claim
13 words
The apparatus of claim 5 wherein said predetermined a.c. voltage level is adjustable.
Claim 8
Dependent Claim
160 words
An a.c. and d.c. power supply for driving a non-linear load in which current over the operating range increases faster or slower than applied voltage comprising: a rectangular wave generator for generating a substantially rectangular waveshape, a push-pull amplifier for amplifying said waveshape, a transformer for receiving the output of said push-pull amplifier at the ends of said transformer primary, and for coupling said output to said load such that the sum of all instantaneous positive and negative a.c. voltages at said load will be approximately zero, a d.c. power source coupled to the center tap of said transformer primary, and d.c. feedback means for comparing the d.c. current at said load produced by the application of a non-symmetrical a.c. voltage to said non-linear load against a first adjustable reference, and for producing and coupling to said rectangular wave generator a correction signal to vary the symmetry of said a.c. waveshape to regulate said d.c. current to a pre-determined level.
Claim 9
Dependent Claim
160 words
An a.c. and d.c. power supply for driving a non-linear load in which current over the operating range increases faster or slower than applied voltage comprising: a rectangular wave generator for generating a substantially rectangular waveshape, a push-pull amplifier for amplifying said waveshape, a transformer for receiving the output of said push-pull amplifier at the ends of said transformer primary, and for coupling said output to said load such that the sum of all instantaneous positive and negative a.c. voltages at said load will be approximately zero, a d.c. power source coupled to the center tap of said transformer primary, and d.c. feedback means for comparing the d.c. current at said load produced by the application of a non-symmetrical a.c. voltage to said non-linear load against a first adjustable reference, and for producing and coupling to said rectangular wave generator a correction signal to vary the symmetry of said a.c. waveshape to regulate said d.c. current to a pre-determined level.
Claim 10
Dependent Claim
57 words
The apparatus of claim 7 further comprising a.c. feedback means for comparing the a.c. voltage at said load against a second adjustable reference, and for producing and coupling to said d.c. power source a correction signal to vary the d.c. power and therefore the amplification of said amplifier to regulate said a.c. voltage to a pre-determined level.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-07-25 | 1981-01-24 | 1981-07-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-07-25 | 1985-01-24 | 1985-07-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-07-25 | 1989-01-24 | 1989-07-26 | $7700.00 | Window Closed / Lapsed |